Jack.



No. 772.238. PATENTED OUT. 11, 1904.

1 I. JEFFERSON.

JACK. v

I APPLICATION FILED FEB. a. 1904. NO MODEL.

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, balls 4. A block 5 is mounted upon the base UNITED STATES PatentedOctober 11, 1904.

PATENT OFFICE.

JACK.

SPECIFICATION formingpart of Letters Patent No. 772,238, dated October11, 1904.

Application filed February 3, 1904.

T0 at whom, it may concern.-

Be it known that I, ISAAC JEFFERSON, a citizen of the United States,residing at Langston, in the county of Logan and Territory of Oklahoma,have invented new and useful Improvements in Jacks, of which thefollowing is a specification.

My invention relates to new and useful improvements in jacks especiallyadapted for railway purposes; and its object is to provide a simpledevice of this character having a supporting-screw which can be readilyrotated in either direction.

- A further object is to provide an operating-lever which can be quicklydetached from the body of the jack.

With the above and other objects in view the invention consists of abase upon which is revolubly mounted a block which engages the screw ofthe jack. This block has teeth upon the periphery thereof adapted to beengaged by the ends of arms pivoted in oppo' site sides of anoperating-lever.

The invention also consists in the further novel construction andcombination of parts hereinafter more fully described and claimed, andillustrated in the accompanying drawings, showing the preferred form ofmy invention, and in which Figure '1 is a perspective view of the jack.Fig. 2 is a top plan view thereof, partly broken away; and Fig. 3 is asection on' line 3 3, Fig. 2.

Referring to the figures by numerals of reference, 1 is a base having anannular flange 2 at the upper end thereof and provided with a circulargroove 3, which forms a race for and also has a race 6 for the receptionof the balls. A sleeve 7 is secured to the block and engages the flange2, and this sleeve prevents the block from becoming accidentallydetached from the base. A screw-threaded passage extends through theblock 5 and is engaged by a screw 8, adapted to. project into anaperture 9, formed in base 1. This screw Serial No- 191,893. (No model.)

block, and the other half is inclosed by ahead 18, which is hinged toone side of 'yoke 11 and is adapted with said yoke to completely inclosethe block. The head and yoke may be secured in position about the blockbymeans of a spring-plate 14:, adapted to engage one or' more pins 15.The sides of the yoke 11 are slotted, as shown at 16, and within theseslots are pivoted arms 17, which extend longitudinally of the lever 12and are normally pressed in opposite directions therefrom by springs 18.The inner ends of the arms 17 normally engage teeth 19, which areproduced in the periphery of the block by the formation of apertures.

When it is desired to raise an object by means of this device, the base1 is placed in position thereunder with the head 10 against the objectto be raised. The block 5is then rotated by oscillating lever 12 and thearms 17 connected thereto. When the lever is swung in one direction,only one arm 17 will engage the teeth on the block, while the other armwill slip thereover, and when the lever is returned to its normalposition one or both of the arms must be pressed toward the lever so asto disengage them from the block. By

providing a lever and arms of the arrangement shown the block can bereadily rotated in either direction, so as to move the screw upward ordownward, as desired, when the block is rotated. To detach the leverfrom the block, it is merely necessary to spring the plate 14 off of thepins 15, and the head 13 can then be swung backward on its hinge. Theballs 1 permit the block to be readily rotated when under heavypressure.

The entire device is very simple, compact, and eflicient.

In the foregoing description I have shown the preferred form of myinvention; butIdo not limit myself thereto, as I am aware thatmodifications may be made therein without departing from the spirit orsacrificing any of the advantages thereof, and I therefore reserve theright to make such changes as fairly fall Within the scope of myinvention.

Having thus fully described the invention, what is claimed as new is 1.The combination with a base having an annular flange, a block supportedby the base and having teeth therearound, and a retaining-sleeve securedto the block and engaging the flange; of a screw engaging the block, alever revolubly mounted upon the block, and oppositely-disposedspring-pressed arms connected to the lever and normally engaging theteeth.

2. The combination with a base having an annular flange, a blocksupported upon the base, and a retaining-sleeve secured to the block andengaging the flange; of a yoke revolubl y mounted upon the block, a headhinged thereto, means for securing the head and yoke together to inclosethe block, oppositely-disposed spring-pressed arms pivoted in the yokeand normally engaging the opposite sides of the block, and a screwrevolubly mounted within the block.-

3. The combination with a base having an 20 ISAAC JEFFERSON.

Witnesses:

HAYWARD I. HARDEN, P. T. ZEIGLER.

